<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>数组的reduce方法</title>
</head>
<body>
  <script>
     const arr=[1,2,3]
     arr.reduce(function(prev,item){
         console.log(prev);
         return prev+item
     },0)
  </script>
</body>
</html>